Contents data for movies, video movies or television programs, etc. are distributed in the state where information such as advertisements, etc. of company cooperative as sponsor are attached by using a recording medium such as a television broadcast, a video tape cassette or a DVD (Digital Versatile Disc), etc. For example, recording media where contents are recorded with advertisements are offered to viewers at low cost in such a manner that advertisements are recorded along with the contents.
In recent years, contents data including audio data and picture data are also delivered through a network by popularization of the so-called Internet. Followed by this, at a website of the Internet, Banner advertisement is provided. This Banner advertisement is an advertisement provided for propaganda at a portion of the website. For example, in the Banner advertisement, the user carries out a click (select) operation by a mouse, etc. so that the web page for propaganda is newly opened. At this time, the number of times in which the Banner advertisement is clicked, i.e., the number of accesses of user also serves as index indicating an effect of the advertisement.
Meanwhile, with the popularization of recording apparatuses such as a video tape recorder, a hard disc recorder or an optical disc recorder, etc., viewers can carry out audition of contents of movies, etc. recorded on the recording medium according to their tastes. In more practical sense, viewers have also been able to carry out the audition of only contents by making use of various functions of the recording apparatus such as skip of reading or CM canceler, etc. For example, as described above, a movie broadcasted by television broadcast can be recorded on the recording medium in the state in which advertisements are included. In this case, in appreciating the main part (compilation) of the movie, viewers can also reproduce only the main part without reproducing an advertisement which is not related to the main part. This approach cannot exhibit effects that the advertisement, etc. brings about. Such a problem similarly applies to copyright management data as copyright information attached to contents such as movie or music, etc., and the viewers can reproduce only the main part (compilation) without reproducing copyright information which is not related to the main part.
Since the Banner advertisement of internet cannot force select operation (click) with respect to user, effect of the Banner advertisement depended upon interest or taste of user.
As a method of delivering contents, there is a method of delivering enciphered contents to respective terminal equipments through internet, etc. to separately carry out charging with respect to a person who desires to conduct viewing of the contents and to provide a cipher key. When the cipher key is offered to a person who carries out viewing, only the cipher key is provided through internet, etc., and any additional value is not added to this cipher key.